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Search: id:A086206
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| A086206 |
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Number of n X n matrices with entries in {0,1} with no zero row and with zero main diagonal. |
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+0
3
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| 0, 1, 27, 2401, 759375, 887503681, 3938980639167, 67675234241018881, 4558916353692287109375, 1213972926354344043087129601
(list; graph; listen)
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OFFSET
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1,3
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FORMULA
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a(n) = (2^(n-1)-1)^n = Sum_{k=0..n} (-1)^k*binomial(n, k)*2^((n-k)*(n-1)).
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MAPLE
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with(combinat): a:=n->(mul((stirling2(n, 2)), j=1..n)): seq(a(n), n=1..10); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 03 2007
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CROSSREFS
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Cf. A055601, A086193.
a(n) = A092477(n,n-1).
Sequence in context: A075081 A017307 A060629 this_sequence A017427 A050644 A048567
Adjacent sequences: A086203 A086204 A086205 this_sequence A086207 A086208 A086209
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KEYWORD
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easy,nonn
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AUTHOR
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Vladeta Jovovic (vladeta(AT)Eunet.yu), Aug 27 2003
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